One application of video technique in the motor vehicle field is that of night vision systems. In this context, heat-sensitive cameras as well as a projection unit may be used, which project the visible images recorded by the camera onto the windshield (so-called head-up displays). U.S. Pat. No. 5,414,439 is an example of such a night vision system. The expenditure for such a night vision system may be considerable, particularly because of the high cost of these components.